English

F(x) = x3 – 2x2 – x + 3 in [0, 1] - Mathematics

Advertisements
Advertisements

Question

f(x) = x3 – 2x2 – x + 3 in [0, 1]

Sum

Solution

We have, f(x) = x3 – 2x2 – x + 3 in [0, 1]

Since, f(x) is a polynomial function it is continuous in [0, 1] and differentiable in (0, 1)

Thus, conditions of mean value theorem are satisfied.

Hence, there exists a real number c ∈ (0, 1) such that

f'(c) = `("f"(1) - "f"(0))/(1 - 0)`

⇒ 3c2 – 4c – 1 = `([1 - 2 - 1 + 3] - [0 + 3])/(1 - 0)`

⇒ 3c2 – 4c – 1 = –2

⇒ 3c2 – 4c + 1 = 0

⇒ (3c – 1)(c – 1) = 0

⇒ c = `1/3 ∈ (0, 1)`

Hence, the mean value theorem has been verified.

shaalaa.com
  Is there an error in this question or solution?
Chapter 5: Continuity And Differentiability - Exercise [Page 112]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 12
Chapter 5 Continuity And Differentiability
Exercise | Q 74 | Page 112

RELATED QUESTIONS

Check whether the conditions of Rolle’s theorem are satisfied by the function
f (x) = (x - 1) (x - 2) (x - 3), x ∈ [1, 3]


Verify Rolle’s theorem for the function f (x) = x2 + 2x – 8, x ∈ [– 4, 2].


Examine if Rolle’s Theorem is applicable to any of the following functions. Can you say some thing about the converse of Rolle’s Theorem from these examples?

f (x) = [x] for x ∈ [5, 9]


Examine if Rolle’s Theorem is applicable to any of the following functions. Can you say some thing about the converse of Rolle’s Theorem from these examples?

f (x) = [x] for x ∈ [– 2, 2]


If f : [– 5, 5] → R is a differentiable function and if f ′(x) does not vanish anywhere, then prove that f (– 5) ≠ f (5).


Verify Mean Value Theorem, if f (x) = x3 – 5x2 – 3x in the interval [a, b], where a = 1 and b = 3. Find all c ∈ (1, 3) for which f ′(c) = 0.


Verify Lagrange's Mean Value Theorem for the following function:

`f(x ) = 2 sin x +  sin 2x " on " [0, pi]`


Verify the Lagrange’s mean value theorem for the function: 
`f(x)=x + 1/x ` in the interval [1, 3]


Verify Langrange’s mean value theorem for the function:

f(x) = x (1 – log x) and find the value of  c in the interval [1, 2].


Verify Rolle’s Theorem for the function f(x) = ex (sin x – cos x) on `[ (π)/(4), (5π)/(4)]`.


Verify Mean value theorem for the function f(x) = 2sin x + sin 2x on [0, π].


The value of c in Rolle’s Theorem for the function f(x) = e x sinx, x ∈ π [0, π] is ______.


The value of c in Mean value theorem for the function f(x) = x(x – 2), x ∈ [1, 2] is ______.


f(x) = x(x – 1)2 in [0, 1]


f(x) = `sin^4x + cos^4x` in `[0, pi/2]`


f(x) = log(x2 + 2) – log3 in [–1, 1]


f(x) = `x(x + 3)e^((–x)/2)` in [–3, 0]


Discuss the applicability of Rolle’s theorem on the function given by f(x) = `{{:(x^2 + 1",",  "if"  0 ≤ x ≤ 1),(3 - x",",  "if"  1 ≤ x ≤ 2):}`


f(x) = `1/(4x - 1)` in [1, 4]


For the function f(x) = `x + 1/x`, x ∈ [1, 3], the value of c for mean value theorem is ______.


If x2 + y2 = 1, then ____________.


The value of c in Rolle’s theorem for the function, f(x) = sin 2x in `[0, pi/2]` is ____________.


If A, G, H are arithmetic, geometric and harmonic means between a and b respectively, then A, G, H are


Value of' 'c' of the mean value theorem for the function `f(x) = x(x - 2)`, when a = 0, b = 3/2, is


Let a function f: R→R be defined as

f(x) = `{(sinx - e^x",", if x < 0),(a + [-x]",", if 0 < x < 1),(2x - b",", if x > 1):}`

where [x] is the greatest integer less than or equal to x. If f is continuous on R, then (a + b) is equal to ______.


P(x) be a polynomial satisfying P(x) – 2P'(x) = 3x3 – 27x2 + 38x + 1.

If function

f(x) = `{{:((P^n(x) + 18)/6, x ≠ π/2),(sin^-1(ab) + cos^-1(a + b - 3ab), x = π/2):}`

is continuous at x = ` π/2`, then (a + b) is equal to ______.


`lim_(x→0) sqrt(1 - cosx)/(sqrt(2)x)` is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×